Power monitoring and metering have long been used in some applications to provide any of a number of items of information to different entities that supply, deliver, and consume power. One common use of such information may be used to determine energy consumption for purposes of billing a user for the power received by that user. One area that is continuing to increase in the amount of power consumption is related to computing facilities that are continuing to house more and more equipment, often referred to as server farms or data centers. Such facilities often have numerous individual pieces of computing equipment that are arranged in racks. Power distribution units have long been utilized to supply power to electronic equipment in such facilities (as well as racks and equipment in many other facilities as well). A conventional power-distribution unit (PDU) is an assembly of multiple electrical “outlets” (also called “receptacles”) that receive electrical power from a source and distribute the electrical power via the outlets to one or more separate pieces of electronic having respective power cords plugged into respective outlets of the PDU. PDUs can also have power cords hard wired to a power source instead of, or in addition to, outlets. PDUs can be used in any of various applications and settings such as, for example, in or on electronic equipment racks, among other applications. A PDU located in a cabinet may be connected to other PDUs or to other devices such as environmental monitors, for example temperature and humidity sensors, fuse modules, communications modules, and the like. Such a PDU and any other PDUs and other devices to which it is connected are commonly enclosed within an equipment rack or equipment cabinet and may be collectively referred to as a Cabinet Power Distribution Unit (CDU).
As mentioned, computing facilities generally include electronic equipment racks, such as standard RETMA racks, that commonly comprise rectangular or box-shaped housings sometimes referred to as a cabinet or a rack and associated components for mounting equipment, associated communications cables, and associated power distribution cables. Electronic equipment is commonly mountable in such racks so that the various electronic devices are aligned vertically one on top of the other in the rack. Often, multiple such racks are oriented side-by-side, with each containing numerous electronic components and having substantial quantities of associated component wiring located both within and outside of the area occupied by the racks. Such racks commonly support equipment that is used in a computing network for an enterprise, referred to as an enterprise network.
In many cases, computing facilities such as server farms or data centers support large networks, referred to as enterprise networks. Enterprise networks exist to support large world-wide organizations and depend on a combination of technologies, e.g., data communications, inter-networking equipment (frame relay controllers, asynchronous transfer mode (ATM) switches, routers, integrated services digital network (ISDN) controllers, application servers), and network management application software. Such enterprise networks can be used to support a large company's branch offices or campuses throughout the world, and, as such, these networks have become mission critical to the functioning of such organizations. Masses of information are routinely expected to be exchanged, and such information exchanges are necessary to carry on the daily business of modern organizations. For example, some international banks have thousands of branch offices placed throughout Europe, Asia and North America that each critically depend on their ability to communicate banking transactions quickly and efficiently with one another and with their respective headquarters.
A typical enterprise network uses building blocks of router and frame relay network appliances mounted in equipment racks. Such equipment racks are distributed to remote point of presence (POP) locations in the particular network. Each equipment rack can include frame relay controllers, routers, ISDN controllers, servers and modems, etc., each of which are connected to one or more power sources. The value of POP equipment is often very substantial, and the number of individual devices can exceed several thousand.
As mentioned, a relatively large number of equipment racks are commonly located in one or more data centers, and may act as hubs for data communications for an enterprise. Additionally, an increasingly common practice is for multiple enterprises to use a computing facility for all or a part of the enterprise computing requirements, such as through the use of a co-location facility. Conventional network management technologies provide relatively little information related to electrical power consumption in a data center or to status of a data center and of equipment racks within such a data center and of components associated with such equipment racks. Energy consumption of data centers can be a source of significant costs for an enterprise, and increasing energy efficiency of data centers could provide a significant cost savings for an enterprise. Furthermore, the ability to accurately measure power provided to identified racks and components within a data center can enable the operator of a data center to accurately bill costs associated with a particular rack or component.